Barrier safety system

ABSTRACT

A barrier safety system ( 3 ) for supporting a barrier rail ( 1 ) between a pair of frangible upright posts ( 2 ) includes a pair of pins ( 8 ) insertable in respective sockets ( 4 ) in the posts, the pins each having a weakened portion designed to break upon the application of a vertically downward load onto the barrier rail within or above a predetermined range. In one embodiment stop members ( 10 ) are provided to vary the distance the support pin may be inserted into the socket for accommodating different sizes of barriers, to thereby ensure that similar leverage is applied to the weakened portion by different sized barrier rails such that they all break the pin when a similar load has been applied to the top of the barrierrail. In another, preferred, embodiment the weakened portion is in the form of a generally ‘V’-shaped notch ( 9   a ) providing a sharply defined fracture point for the pin when under load.

[0001] This invention relates to barrier safety systems for usetypically, but not exclusively, in equestrian eventing.

[0002] In equestrian eventing and similar activities a horse and riderhave to negotiate barriers which may typically be comprised of logs ofwood or barriers of corresponding shape made of synthetic materials suchas plastics and glass fibre composite. In each case, the barrier has tobe sufficiently strong to withstand the shock of impact by a horsewithout breaking, even if the barrier is mounted in such a way that acollision into it by a horse and rider would not normally dislodge orbreak it. This presents a problem as a potential safety hazard for, inparticular, the rider. Several fatalities have occurred by horses notnegotiating such barriers successfully, when the rider is catapultedforwards and the horse then rolls over the barrier onto the rider.Although it would be possible to alleviate this hazard by the use oflightweight, bendable or breakable barriers, this is deemed toconsiderably lessen the natural thrill of eventing.

[0003] This problem is exacerbated by the lack of uniformity of many ofthe materials used for such barriers and support posts etc. For example,if such are made from wood by cutting down trees and branches etc thebarrier itself will have a natural taper arid, depending upon the woodfrom which it is made and e.g. support posts used therewith, thestiffness and hardness of the wood provide inherent variables. Anotherproblem is that these barriers can be of widely varying diameters,typically between 150 mm and 300 mm, so that it is difficult to adoptany common standard in the event that safety features are to be adoptedwhich would prevent or inhibit the injury of riders in suchcircumstances.

[0004] The present invention is derived from the realisation that itwould be advantageous to have a barrier safety system which retains thethrill of eventing and other similar activities but which provides forthe barrier to be removed as an obstacle upon the application of avertically downward load within or above a given range, even though avariety of different types and sizes of barrier rails are used.

[0005] According to the invention there is provided a barrier safetysystem for supporting a generally horizontally disposed barrier rail ofgenerally circular section between a pair of generally verticallydisposed upright members, such as posts, the system comprising a pair ofsockets, one for each upright member and a pair of barrier rail supportpins, one for each socket, each support pin being insertable at one endinto a respective socket and including near to that end a weakenedportion, at which point the support pin will break upon the applicationof a vertically downward load onto the barrier rail within or above adesired range of loads.

[0006] Conveniently, the weakened portion of the support pin for eachsocket comprises a waist region which is designed to break if avertically downward load is applied to the pin within or above a givenrange, such as between 6 kN and 7.5 kN and above.

[0007] In a preferred embodiment of the invention one or more stopmembers are provided between the weakened portion and the socket to varythe distance the support pin may be inserted into the socket so as toaccommodate different sizes of barrier rails. This ensures that similarbending moments and hence leverages apply to the weakened portion eventhough, barrier rails of different diameters are used, such that theyall break the pin when the same or a similar load has been applied tothe top of the barrier rail by e.g. a horse falling onto it.

[0008] This has the advantage in that by being able to adjust thedistance by which each support pin extends out of its respective socketit is possible to easily and quickly compensate for different diametersof barrier rail so that, effectively, the distance between the weakenedportion of the support pin and the point of contact with the bottom ofthe barrier rail and the support pin can compensate for what otherwisewould be an increase in the leverage available to break the support pinby a barrier rail of relatively large diameter as compared to one of asmaller diameter, and vice versa. In this way breakage of the pin ismore likely to occur within the desired range irrespective of whether abarrier rail of relatively large diameter, say 250 mm, is being usedinstead of a barrier rail of, say, 170 mm diameter.

[0009] Conveniently, the stop members comprise stop pins receivable inrespective bores in the support pin for each socket, the bores beingsubstantially at right angles to the major axis thereof.

[0010] Each support pin is preferably made of a substantiallynon-ductile material, such that energy is not absorbed by plasticbending of the pin, but that the pin snaps when the desired load limitis reached. It has been found that a suitable material is an aluminiumalloy ref 6061T6 made in accordance with BS 8118 Part 1 has thenecessary properties, this alloy being composed of aluminium alloyedwith 0.69% silicon, 0.41% iron, 0.22% copper, 0.05% manganese, 0.90%magnesium, 0.15% chromium, 0.011% titanium and 0.01% zinc.

[0011] Conveniently, the socket for each pin is in the form of a tubefor receiving a respective support pin, and a flange may be provided atone end thereof, the flange being in the form of a large plate adaptedto be secured to an upright member, which may be a wooden post. Theflange plate may conveniently include apertures for securing it to anupright member, e.g. by bolts etc.

[0012] In a preferred embodiment of the invention each pin is providedwith a marker to assist in setting the pin within a respective socket tothe correct distance relative to the diameter of the barrier rail, themarker being aligned vertically below the centre of the barrier rail. Inaddition, the weakened portion of the pin is provided by means of asharp, radially disposed, “vee”-shaped notch, thereby providing acorrespondingly sharp fracture point.

[0013] The invention will now be described, by way of example only, withreference to the accompanying drawings in which:

[0014]FIG. 1 shows in part section a barrier safety system according toa first embodiment of the invention, and

[0015]FIG. 2 shows in part section a barrier safety system according toa second embodiment of the invention.

[0016] Referring firstly to FIG. 1, a barrier safety system forsupporting one end of a barrier rail 1 (shown partially in brokenoutline) is supported on an upright member in the form of a wooden post2 (only part of which is shown), the other end of the barrier 1 beingsupported in the same manner on another upright post.

[0017] The barrier safety system shown generally at 3 includes on thisend of the barrier 1 a socket 4 having an integral flange 5 includingapertures (not shown) through which respective bolts 6 and 7 can securethe socket 4 to the post 2, the relatively large size of the flange 5helping to stabilise the positioning of the socket 4 within the post 2and therefore helping to prevent or inhibit any movement thereof.

[0018] The barrier safety system 3 also includes an elongated generallycircular support pin 8 made of a substantially non-ductile material suchas aluminium alloy (BS ref. 6061T6) and includes a weakened portion 9 inthe form of a waist which, as is explained in further detail later, isdesigned to fracture upon the imposition of a vertically downward loadonto the pin 8 at, in this example, the point of contact ‘A’ of thebarrier rail 1 with the pin 8.

[0019] The pin 8 is secured in its selected position by means of a stoppin 10 which is slidingly received in staple 11 fixed to the flange 5,and through a correspondingly shaped bore 12 through the support pin 8,there being two other bores 13, 14 through which the stop pin 10 mayalso be inserted if preferred.

[0020] In the position illustrated, it will be appreciated that avertically downward load acting at the point of contact “A” from thebarrier rail 1 to the support pin 8 will induce a turning moment orleverage effect around the weakened portion 9. In tests using a 250 mmdiameter barrier rail 1 where the diameter of the support pin 8 was 30mm, the weakened portion 9 having a 26 mm diameter and being positioned45 mm from the major plane of the flange 5, failure of the support pin 8at the weakened portion 9 occurred with a vertically downward load of6.09 kN.

[0021] Using a barrier rail 1 having a diameter of 200 mm and insertingthe support pin 8 into the socket 4 up to the point when the stop pin 10can be inserted into the bore 13 and into the staple 11, this beingapproximately 30 mm from the major plane of the flanges, where the pointof contact of the barrier rail 1 with the support pin 8 would then occurat point ‘B’ (relative to the flange 5), it was found that the supportpin 8 failed at the weakened portion 9 under a failure load of 6.90 kN.Similarly, using a barrier rail 1 of only 180 mm diameter and slidingthe support pin 8 further into the socket 4 up to the point where thestop pin 10 can be inserted into the bore 14 and the staple 11, thisbeing approximately 15 mm from the weakened portion 9, it was found thata load applied at position C representing the point of contact of thebarrier rail 1 with the support pin 8, a vertically downward load of6.47 kN produced failure of the support pin 8 at the weakened portion 9.

[0022] Hence, in this embodiment, it will be apparent that bycompensating for what would otherwise be significantly different turningmoments about the weakened portion 9 through the use of barrier rails ofdifferent diameters, it is possible to provide a barrier safety systemfor use with a range of barriers of different diameters using the samesupport pins 8, suitably adjusted as to depth of entry into therespective sockets 4, in which failure of support pin 8 can be expectedabove a given threshold.

[0023] Through the use of a relatively large flange 5, which essentiallystabilises the position of the socket 4, and the use of a substantiallynon-ductile material for the support pin 8, substantially all of theenergy from the vertically downward load imposed by, typically, a horselanding on top of the barrier rail 1 can be focused on the weakenedportion 9 of the support pin 8, irrespective of the diameter and weightof the barrier rail 1 such that even if it is made out of relativelylightweight materials, such as tubular aluminium, it will still providethe same end result i.e. a failure of one or both the support pins 8.

[0024] Referring now to FIG. 2, this shows a second, preferred,embodiment of barrier safety system shown generally at 3 a in which thesocket 4 a is in the form of a thickened tube, part of which is shown insection for clarity. In tests it has been found that very satisfactoryresults can be obtained by the use of such a relatively thick walledsocket which dispenses with the need for the flange 5 of FIG. 1 and alsomakes it easier to fit it within the post 2, by simply driving it into asuitably sized bore.

[0025] The pin 8 a in this embodiment of the invention also includes aweakened portion in the form of a radially disposed “vee”-shaped notch 9a which provides a more sharply defined fracture point than the waist 9of FIG. 1. In addition, in order to assist in locating the correct depthwithin the socket 4 a the pin 8 a must be inserted, a marker in the formof a radially disposed groove 15 is provided. This allows a personsetting up the safety barrier system to insert the pin 8 a into thesocket 4 a, offer up the barrier rail 1 to the post 2 and then to adjustthe depth of insertion of the pin 8 a so that the marker 15 liesimmediately beneath the centre of the rail 1, at which point a stopmember in the form of a pin (not shown) is inserted into one of thebores 12, 13 or 14, the choice of which being dictated by the diameterof the barrier rail 1 which, in the case of that shown in FIG. 2, isbore 14. However, as will be apparent, in the event of the barrier rail1 being of a larger diameter, the pin 8 a and hence marker 15 would needto be moved to the right, thereby exposing, progressively, bore 13 and,for the largest diameter barrier rail 1 bore 12. In this embodiment, astop member in the form of a stop pin (not shown) is inserted into abore 16 in one side of the socket 4 a and, following alignment with arespective bore 12, 13 or 14 in the barrier rail support pin 8 a, isthen inserted into a second bore 17 on the other side of the socket 4 ato complete the assembly, thereby preventing the support pin 8 a fromaccidentally moving in either axial direction and thus ensuring that thefracture point provided by the notch 9 a remains a constant distancefrom the point of contact with the barrier rail 1.

[0026] Although two embodiments of the invention have been shown, inboth of which the bores 12, 13 and 14 into which correspondingly shapedstop members may be inserted to adjust the effective length by which thesupport pins project from their respective sockets, nevertheless it willbe apparent that other means of achieving this objective may be adoptedwithout departing from the spirit or scope of the invention. Similarly,although pins and respective sockets are preferably circular incross-section it will be understood that other shapes may be adopted asmay also other forms of weakened portions for the pins, again withoutdeparting from the spirit or scope of the invention.

1. A barrier safety system for supporting a generally horizontallydisposed barrier rail of generally circular section between a pair ofgenerally vertically disposed upright members, the system comprising apair of sockets, one for each upright member and a pair of barrier railsupport pins, one for each socket, each support pin being insertable atone end into a respective socket and including near to that end aweakened portion wherein the support pin will break upon the applicationof a vertically downward load onto the barrier rail within or above adesired range of loads.
 2. A barrier safety system according to claim 1wherein the weakened portion of the support pin for each socketcomprises a waist region.
 3. A barrier safety system according to claim1 wherein the weakened portion of the support pin for each socketcomprises a generally ‘V’-shaped notch defining a generally sharpfracture point for the pin when under load.
 4. A barrier safety systemaccording to claim 1, wherein one or more stop members are providedbetween the weakened portion and the open end of the socket to vary thedistance the support pin may be inserted into the socket foraccommodating different sizes and weights of barrier rails, to therebyensure that different leverage is applied to the weakened portion bydifferent sized barrier rails, such that they all break the pin when thesame or a similar load has been applied to the top of the barrier.
 5. Abarrier safety system according to claim 4 wherein the stop memberscomprise stop pins receivable in respective bores in the support pin foreach socket substantially at right angles to the major axis thereof. 6.A barrier safety system according to claim 1 wherein each support pin ismade of a substantially non-ductile material.
 7. A barrier safety systemaccording to claim 6 wherein the substantially non-ductile material isaluminium alloy.
 8. A barrier safety system according to claim 1 whereinthe socket for each pin is in the form of a tube for receiving arespective support pin, and a flange is provided in the form of a largeplate adapted to be secured to an upright member.
 9. A barrier safetysystem according to claim 8 wherein the flange includes apertures forsecuring the flange to an upright member by connectors.
 10. (Cancelled)11. (Cancelled)